Commit 215eb9f9 authored by Liang Chen's avatar Liang Chen Committed by Jakub Kicinski
Browse files

veth: Avoid NAPI scheduling on failed SKB forwarding 



When an skb fails to be forwarded to the peer(e.g., skb data buffer
length exceeds MTU), it will not be added to the peer's receive queue.
Therefore, we should schedule the peer's NAPI poll function only when
skb forwarding is successful to avoid unnecessary overhead.

Signed-off-by: default avatarLiang Chen <liangchen.linux@gmail.com>
Link: https://lore.kernel.org/r/20230824123131.7673-1-liangchen.linux@gmail.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent bebfbf07

drivers/net/veth.c

+2 −3
Original line number Diff line number Diff line
@@ -373,14 +373,13 @@ static netdev_tx_t veth_xmit(struct sk_buff *skb, struct net_device *dev) 
	if (likely(veth_forward_skb(rcv, skb, rq, use_napi) == NET_RX_SUCCESS)) {

		if (!use_napi)

			dev_lstats_add(dev, length);

		else

			__veth_xdp_flush(rq);

	} else {

drop:

		atomic64_inc(&priv->dropped);

	}



	if (use_napi)

		__veth_xdp_flush(rq);



	rcu_read_unlock();



	return NETDEV_TX_OK;